Sabah, in Borneo's far north, brings together lush rainforests – prime orangutan habitat – with some of the world's most phenomenal scuba diving and adventurous trekking. More excellent diving awaits south of the Indonesian border on Kalimantan's east coast, and there are plenty of jungle adventures to be had inland, along and between Kalimantan’s major rivers. On Borneo's northwest coast, Sarawak is home to some of the world's largest caves, as well as the island's most accessible national parks. Based in the sophisticated but laid-back city of Kuching, you can take day trips to see orangutans, hike in the jungle and visit longhouse communities. Tiny Brunei, with a tempo and culinary customs all its own, offers visitors pristine rainforest and fascinating architecture – from opulent mosques to the world's largest water village.
Hiking & Trekking
Climbing Mt Kinabalu
The highest mountain in Borneo is an endurance test awaiting the fit and willing. Scale it on a two-day trek and throw in some via ferrata adventure near the summit for the extra challenge and adrenaline.
Spectacular Semporna Archipelago
With clouds of marine life, including hammerhead sharks, parrotfish and green and hawksbill turtles, the diving at Sipadan in the Semporna Archipelago is some of the finest in the world, as is the muck diving around Mabul and Kapalai islands.
Swinging through the canopy comes our distant ginger relative – to glimpse one of these primates is to be reduced to grinning awe. The Sungai Kinabatangan is one of the best places in the world to see wild orangutans up close.
Hiking & Trekking
There is no shortage of places to take a stroll through Sarawak's equatorial rainforest, but the cooler air of the remote Kelabit Highlands is perfect for an exhilarating trek through the jungle from Bario to Ba Kelalan.
Caving at Mulu
Sarawak is home to a number of impressive caverns with stalactites and bats, but for sheer size and spectacle you can't beat the caves of Gunung Mulu National Park, renowned for the gigantic Deer Cave and the 700m-long Sarawak Chamber.
Wild jungle animals, including proboscis monkeys, bearded pigs and families of long-tailed macaques, are easy to spot on the rocky peninsula of Bako National Park, where hiking trails lead through rare lowland ecosystems with pitcher plants and orchids.
Mosques, Palaces & Stilt Villages
Step inside Bandar Seri Begawan's two opulent 20th-century mosques for the sumptuous decor, visit the sultan's palace to see how the royals live, or catch a speedboat to Kampong Ayer, a traditional Malay stilt village – the world's largest.
Night Markets, Strip Malls & Coffee Shops
Bruneians live to eat. Whether you're slurping ambuyat (sago gloop with spicy dipping sauce), munching soft-shell crab eggs Benedict or fiery Korean chicken wings, or sipping a perfect cup of gourmet coffee, BSB's dining scene has something for all palates.
Ulu Temburong National Park
The sultanate has done a fine job of preserving its tracts of primary jungle, especially at Ulu Temburong. Enter it by an exhilarating longboat ride, climb to a canopy walkway above the forest and swim in its waterfalls.
Hiking & Trekking
The easiest area for jungle exploration – with a wide range of guides available – is the stunning Pegunungan Meratus (Meratus Mountains), using Loksado as base camp.
Kalimantan's rainforests will exceed your wildest dreams. A good guide can help you identify gibbons, macaques, flying squirrels, monitor lizards, crocodiles and giant butterflies. Kutai and Gunung Palung national parks are your best bet for spotting truly wild orangutans, but Tanjung Puting is where you’re guaranteed to see them.
In the Derawan Archipelago, surrounded by the Celebes Sea, you can swim in coral-rich water with giant green turtles, manta rays, myriad reef fish, sharks and whales. Borneo's best-kept secret!